Signaling system for train-despatching.



G. BROWN.

SIGNALING SYSTEM FOR TRAIN DESPATOHING.

APFLIGATION FILED MARS 1911.

.Eatented Mar. 16, 1915.

0 Z ma; W

Q E R H n n WW3 cancers: snow, or nnoomlrn, new "roan; nssranch rowuss-nan ELECTHl-J comanr, or new YORK, n. Y.,. a coaeoaaaron ortremors.

. ere-Nannie srsrsra res rnarn-nhsrarcmne.

Specification of Letters Patent.

easem nt/tea ac, aeaa Application filed Hatch 31, 1911. Serial 230.6181188.

To all whom it may concern 7 Be it known that I, GREGORY Brown, citizenof the United States, residing at Brooklyn, in the countyof Kings andState or New York, have'invented a certain new andv 'useful Improvementin Signaling System 5 ing systems for train despatching wires wherein aplurality of way stations located upon the same line are each providedwith a step-by step selective device adapted in response to a certainpredetermined number of unldirectional current impulses of a givencharacter impressed upon the line at the sending station to close acircuit for a local signal which notifies the attendant at theparticular station that he-is wanted.

v The object of this invention is to provide means in connection: withsuch a system whereby a signal, distinctive from the'selectivelyoperated signal, may be connected with the line wires at each'of the waystations and operated by current impulses over the line which will notaffect the selectors and which signals will not becperated by'thecurrent impulses that operate said selectors. j

It is customary on train wires at certain periods during the day tonotify the station operators of the correct time. Where Morse is'used itis the general practice to spell out the word time at a predeterminedtime and at a certain interval after this word has been sent over theline to send out, from a relay in a time wire, a predetermined number ofcurrent impulses, each impulse being sent out at a given instant andreceivcd on the ordinary Morse sounder.

ln'a'ccordance with this invention there is provided at each of the waystations a signal which is operable in response to short currentimpulses of alternate polarity over the line, which current impulseswillnot attors.

feet the selectors and which signals will not be operated by the'unidirectional impulses which operate the selectors, means beingprovided at the sending or despatching station operating in connectionwith the source ofcurrent at the sending station and the timesendingrelay for impressing upon the line the current impulses to which saidsignal is responsive,

The drawing is a diagram illustrating the arrangement of theapparatus-and circuits,

In the drawing, 1 and 2 designate the line wires, Athe despatchersstation, and

B, C, D and E way stations on the line. W

Retardation coils 3, l and 5 are connected in the line for the purposeof smoothing out or graduating the current impulses which are sent overthe line. A condenser 6 is bridged across the line between theretardation coil 3 and the coils 4 and 5 which assists in the gradualemission and extinction of the current impulses.

At each or the way stations there'is located a selector mechanism 10comprising a slow and quickacting magnet 11 and 12 and a ratchet wheel13 controlled thereby, said ratchet wheel having attached thereto acon-- tact arm 14 adapted in the rotation of said ratchet wheel to bebrought into register with a contact 15. The registering of the contacts14 and 15 completes a circuit through a vibrating bell 16 for callingthe operator at the way station to his telephone.

The contacts 15 of each selector closed each in response to a differentnumber of impulses depending upon the distance of each substation fromthe despatchers station. The line wires 1 and 2 are connected through adouble pole, double throw switch 19 with normally open contacts 20 and21 of an impulse relay 22, the contact levers 23 and. 24lof which areconnected with the opposite poles of a battery '25. Animpulsetransmitter 26 with a condenser and resistance in shunt with the impulserelay 22 and a local battery 27-is adapted to intermittently closethecircuit through the relay 22 to send inipulsesjover the line foroperating the selec- There' may be one sending key for each way stationon the line or there may be a master sender which may be adjusted tocall any particular selector.

Located at each of the way stations is a non-biased polarizedringer 30which is bridged across the line wires 1 and2in series with the selectormagnets 11 and 12. This ringer operates in response to alternatingcurrent impulses over the line Wires 1 and 2.

tacts 44 and 45 of a relay 46 with the opposite pole of the battery 25from that with Whichthe conductor 43 is connected. The relay 46 is anordinary telegraphic relay connected with a telegraph line which mayterminate in or pass through the despatchers oiiice and is adapted toreceive time signals from the time sending ofiice in the same manner ason any ordinary telegraph system. The method of sending time.

signals over telegraph lines is old and well known in the art and doesnot require detailed description. With this arrangement the current fiowupon operation of the relay 46 in response to time signals will bethrough one-half of the-primary winding in one direction when the relay46. is energized and through the other half of said primary winding inthe opposite direction when said relay 46 is deenergized. The effect ofthis is that a greater variation of the magnetic lines of force isproducedin the transformer than would be obtained if a straight circuitwas merely made and broken through the primary winding 41 of thetransformer, thus producing an alternating current in which the positiveand negative values are approximately equal.

Briefly stated, the operation of the parts for closing the circuitthrough the local signal 16 is as follows: Assuming that it is desiredto signal the operator at way station B, the idespatcher operates thekey 26 to close the local circuit through the impulse relay 22 theoperation of which sends impulses from the battery 25 over the line tooperate the selector 10. The first of the impulses sent out will be ofsufiicient length to cause the operation of the slow-acting or holdingmagnet, the succeeding impulses being short ones with-insufiicient timetherebetween to permit further operation or release of the olding magnetbut sufiiciently long to operate the quick-acting or stepping magnet. Vihena sufficient number of impulses have been sent to close the contact15 the circuit from the battery 25 to the line wires 1 and 2" will bemaintained closed a suiiicient length of time to permit the ringing ofthe bell 16.

When it is desired to send time signals over the line the switch 19 isthrown into position to bridge the transformer secondary I across theline wires 1 and 2. When this circuit is completed and the relay 46 isoperated by current impulses over the time circuit, circuits will becompleted from the battery 25 first throughone-half'of the transformerrimaryand then through the other half. T e current through these twopaths will be in opposite directions and will cause a change in themagnetic flux of the transformer which will cause an alternating currentto flow: over the line in which the positive and negative values areapproximately equal. Thus there will be sent over the line alternatingcurrent impulses as the relay 46 is energized and denergized. Theseimpulses will be only of sufiicient duration to operate the polarizedringer 30 to cause it to tap once for each impulse and will not causethe operation of the slow-acting magnet of the selector. With thisarrangement the current impulses. on the line will be prolonged only asuflicient length of time to 'insure the operation of the ringer 30regardless of the length of time either of the contacts of the relay 46is closed.

As is the case different codes are employed in sending out the timesignals, that is to say, the length of time during which current is onthe line varies in different systerns, there being some cases where thecurrent impulse is on the line four-fifths of a is'intermittently openedby the operation of said impulse relay, said non-inductive resist- -ancebeing for the purpose of providing a discharge path'for the retardationcoils 3, 4 and 5 and the condenser 6 on heavily loaded lines. Condensers62, 62 and noninductive resistances 63, 63 are bridged around thecontacts 20 and 21 of the relay 22 to prevent excessive sparking whenthe circuit'is opened at these contacts. Condensers 65 and 66- arebridged around the contacts 44: and 45 of the relay46 for the same pur-I claim: I v 1. In a signaling system in combination, a

telephone-line, a polarized signaling device in bridge of said line, asource of direct current, inductive means for connecting said source ofcurrent with said line wires, a tele-f k graph line, and meanscontrolled by impulses over said telegraph line for interrupting theprimary circuit of said inductive means.

2. In a signaling system in combination, a

telephone line, a polarized signaling device in bridge of said line, asource of direct ourmenarcrent, an induction coil having its primaryconnected with said current supplying means and its secondar with saidline wires, a telegraph line, an means controlled by impulses over saidtelegraph line for successively reversing the current flow through saidrimary winding.

3-. n a signaling system the combination with a telephone line, apolarized signaling device in bridge of said line, current supplyingmeans, an inductive device, the primary of said inductive device beingdivided into two parts and the secondary thereof connected with saidline wires, a telegraph line and means actuated by impulses over saidtelegraph line for successively connecting the two'parts of saidinductive device primarywith said current supplying means.

telegraph line.

4. In a signaling system in combination, a telephone line, a polarizedsignaling device in bridge of said line, current supplying means, aninduction coil having a divided primary, the secondary thereof beingconnected with said line wires, a telegraph line and a relay in saidtelegraph line having a front and back contact through which the twoparts of said primary winding are separately connected with said sourceof energy in response to impulses impressed upon said In Witnesswhereof, I hereunto subscribe my name this 30th dag G EGORY BROWN.Witnesses:

IRVING MACDONALD, MORGAN WASHBURN, Jr.

of March, A. D. 1911.

